1. Field of the Invention
This invention relates to a novel compound and use thereof for insect control, and more particularly to the novel pheromone compound 6,12-dimethylpentadecan-2-one and its use as an attractant, disruptant, and monitoring agent for the banded cucumber beetle.
2. Description of the Art.
Diabrotica is a large New World genus of galerucine chrysomelids that includes several pests. The catalog of Wilcox (Coleopterorum Catalogus Supplementa. (Ed. 2) Galerucinae luperini: Pars 78, Fisc. 2: 296-431 (1972)) lists 338 species in three groups; the virgifera and fucata groups includes pests. The banded cucumber beetle (BCB), Diabrotica balteata LeConte (Coleoptera: Chrysomelidae), is an economically important pest of vegetable and field crops, particularly sweet potato and seedling vine crops such as squash, melon, and cucumber (cucurbits). It occurs from the southern United States to Colombia, Venezuela, and Cuba. The adults feed on foliage and pollen while the larvae, which are the most damaging stage, feed on plant roots or tubers. They seriously threaten potato and sweet potato production in tropical and subtropical climates by scarring the tubers or edible roots which lowers market value or by subjecting the tubers/roots to infection by rot organisms. Larval feeding on curcurbits, corn, tomato, a wide range of peas and beans and many other vegetable hosts can reduce the vigor of the plant and thus reduce yield. Control of this pest involves the use of broad spectrum pesticides that often cause outbreaks of secondary pests or present risks of ground water contamination. Therefore, it is highly desirable to control BCB populations by other means.
The continued search for alternatives to the widespread applications of insecticides has led to the investigation of sex attractants as potential agents for use in integrated pest management. programs. A number of economically important insects are currently monitored, partially controlled, or completely controlled by use of their own specific pheromone. The use of pheromones has also been reported for locating, surveying, or monitoring pest populations at levels not otherwise detectable. In the case of the BCB, the lack of identification and availability of the BCB pheromone has precluded application of this technology to the treatment of this pest.
Cuthbert and Reid (Journal of Economic Entomology 57: 247-250 (1964)) reported that a natural sex attractant was produced by BCB females and that field traps baited with either adult virgin females or with their abdominal extracts attracted BCB males from distances as far as 49 feet. Schwarz et al. (Journal of Economic Entomology 64: 769-770 (1971)) carried out chemical studies on the active fraction of an extract of BCB adult virgin females. From their studies, they concluded that the BCB sex attractant included n-dodecenyl, ethylene epoxy, and methyl ketone moieties. They were unable to complete the structure elucidation.
Sex pheromones for some species of Diabrotica have been reported. Guss et al. (Journal of Chemical Ecology 9: 1363-1375 (1983) and U.S. Pat. No. 4,474,991) identified the R-enantiomer of 10-methyl-2-tridecanone as the sex pheromone of the southern corn rootworm (SCR), D. undecimpunctata howardi Barber. Guss et al. (Journal of Chemical Ecology 8: 545-556 (1982) and U.S. Pat. No. 4,734,5214) identified 8-methyl-2-decanol propanoate as the sex pheromone for the western corn rootworm (WCR), D. virgifera virgifera LeConte. The compound has been shown to be an effective attractant for adult males of the WCR; the northern corn rootworm, D. longicornis barberi Smith and Lawrence; and the Mexican corn rootworm, D. virgifera zea Krysan and Smith.